S.D. Codified Laws § 9-43-116
If general obligation bonds are authorized, issued, and sold and the proceeds expended for the purpose of any local improvements of a type for which assessments may lawfully be levied, and if assessments have been levied on account of such improvements in the manner prescribed by law, special assessment bonds may be issued in anticipation of the collection of the assessments and may be transferred and appropriated to the debt service fund for the general obligation bonds, in reimbursement of all or any part of the sum expended. The amount of bonds transferred and appropriated may not exceed the sum expended, less any portion of the cost of the improvements to be assumed by the municipality. Any assessment bonds not transferred may be sold to third parties to provide additional moneys for financing the improvement.
SDCL 9-43-116